Tuesday, May 12, 2015

Member in the News: Jesse Tack

Troubling new research says global warming will cut wheat yields

Observant aliens visiting Earth and studying its civilizations would probably be pretty obsessed with wheat. They couldn’t fail to note how staggeringly many people we feed with the crop on this planet.

“Wheat is one of the main staple crops in the world and provides 20% of daily protein and calories,” notes the Wheat Initiative, a project launched by G20 agricultural ministers. “With a world population of 9 billion in 2050, wheat demand is expected to increase by 60%. To meet the demand, annual wheat yield increases must grow from the current level of below 1% to at least 1.6%.”

That’s why the punchline of a new study in the Proceedings of the National Academy of Sciences is pretty troubling. A warming climate, it suggests, could drive wheat yields in the opposite direction – down — in the United States and, possibly, elsewhere.

“The net effect of warming on yields is negative,” write Jesse Tack of the agricultural economics department of Mississippi State University and two colleagues, “even after accounting for the benefits of reduced exposure to freezing temperatures.”

That’s no small matter, the study notes, in that wheat is “the largest source of vegetable protein in low-income countries.”

The study compared results from nearly 30 years of winter wheat trials across Kansas — a state that produced $2.8 billion worth of wheat crop in 2013 — with data on weather and precipitation. Winter wheat grows from September to May and faces two major temperature-related threats during this cycle — extreme winter cold, and extreme spring heat.